The towers and keepers’ houses of the 23 Maine lighthouses from Biddeford to Maine will be open to visitors from 9 a.m. to 3 p.m. for guided or self-guided tours.

The list of participating lights and their specific accessibility times and details can be seen at http://ift.tt/1KH3Ece.

This event is the largest of its kind in the country and includes lights not normally open to the public, including: Owls Head Light in Owls Head; Curtis Island Light in Camden Harbor; Dyce Head Light in Castine; Monhegan Island Light on Monhegan Island; Portland Breakwater (Bug Light) in South Portland; and the tower at West Quoddy Head Light in Lubec.

“We sincerely hope visitors take full advantage of this unique opportunity to get an inside glimpse of some of Maine’s most beautiful and historic navigational landmarks,” said Lt. David Bourbeau, chief of waterways management at Coast Guard Sector Northern New England.

Some light stations may have limited accessibility or special restrictions.